3) Two atoms have identical electron configurations. Which statement about the atoms is true?
a) They have the same chemical properties.
b) They must have the same mass.
c) They must have the same number of neutrons.
d) They could be atoms of different elements in the same group.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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